It's been stated more than once that WWIII will most likely be cyber-based, such as dismantling a country's entire infrastructure via cyber weapons. And don't think for a moment this doesn't mean murdering people.
A report at bits.blogs.nytimes.com notes that foreign hackers have cracked into the U.S. Department of Energy's networks 150 times; they've stolen blueprints and source code to our power grid as well. Some say they have the capability to shut down the U.S.
The bits.blogs.nytimes.com article goes on to say that cyber warfare could result in death by the masses, e.g., water supply contamination of major cities, crashing airplanes by hacking into air traffic control systems, and derailing passenger trains. So it's no longer who has the most nuclear missiles.
The list of successful hacks is endless, including that of a thousand energy companies in North America and Europe and numerous gas pipeline companies. The U.S.'s biggest threats come from Russia and China.
So why haven't they shut down our grid and blown up furnaces at hundreds of energy companies? Maybe because they don't have the ability just yet or maybe because they don't want to awaken a sleeping giant. To put it less ominously, they don't want to rock the boat of diplomatic and business relations with the U.S.
Well then, what about other nations who hate the U.S. so much that there's no boat to be rocked in the first place? The skills to pull off a power grid deactivation or air traffic control infiltration by enemies such as Iran or Islamic militants are several years off.
On the other hand, such enemies don't have much to lose by attacking, and this is worrisome. It is these groups we must worry about. They're behind alright, but they're trying hard to catch up to Russia and China. For now, we can breathe easy, but there's enough going on to get the attention of Homeland Security and other government entities.
Recent attacks show that these bad guys in foreign lands are getting better at causing mayhem. At the same time, the U.S.'s cyber security isn't anything to brag about, being that very recently, some white hat hackers had tested out the defenses of the Snohomish County Public Utility District in Washington State. They infiltrated it within 22 minutes.
Another weak point in our defenses is the component of pinning down the source of major hacking incidents. So if WWIII becomes real, the U.S. won't necessarily know where the attack came from.